Compressor discharge valve



Oct, 17, 1933. KLABQN 1,931,198

'CONPRES SOR DI S CHARGE VALVE Filed Nov. 26, 1930 2 Sheets-Sheet 1 vOct. 17, 1933. J. KLABON COMPRESSOR DISCHARGE VALVE 2 Sheets-Sheet 2Filed Nov. 26, 1930 @f/m'zr zfozoTK/awl Patented Oct. 173 1933 I UNITEDSTATES PATENT. OFFICE COMPRESSOR DISCHARGE VALVE John L. Klabon,Detroit, Mich, assignor to Norge Corporation, Detroit, Mich., acorporation of Michigan Application November 26, 1930 Serial No. 498,219

3 Claims.

This invention relates to discharge valves for compressors and hasspecial reference to improved quietness of operation when flapper valvesare used in connection with rotary compressors.

The flapper valves heretofore in use have been found desirable for theirefficiency in operation in connection with rotary compressors butundesirable from a noise standpoint when such is provided for the escapeof lubricant trapped between the rotor and the cylinder at the end ofthe compression period, thus preventing a sudden rise in pressure,,witha consequent great improvement in the quietness of operation of thecompressor.

It is a further-object of this invention to provide an improved andsimplified discharge valve arrangement for rotary compressors that willbe economical to manufacture and assemble and that will not requireexcessively skilled servicing for maintenance.

Other and further important objects of this invention will be apparentfrom the disclosures in the specification and the accompanying drawngs.o

This invention (in a preferred form) is illustrated in the drawings andhereinafter more fully described.

I On the drawings:

Fig. 1 is a central longitudinal section, part-, ly in elevation, of arotary compressor to which a discharge valve embodying one form of thisinvention has been applied.

Fig. 2 is an enlarged plan view of one face of the compressor cylinderproper, the oil reservoir housing having been removed.

Fig. 3 is an enlarged fragmentary section of the compressor on the lineIII-III of Fig. 1,

to show the discharge passage leading to the valve.

Fig. 4 is an enlarged fragmentary? section through the compressor endcover and valve housing, taken on the line IV-IV of Fig. 2.

- Fig. 5 is an enlarged cross-section on the line VV of Fig. 2.

Fig. 6 is a section on the line VI-VI of Fig. 4. Fig.- '7 is an enlargedfragmentary plane view of the compressor cylinder adjacent the blade,

with the cylinder cover in place but with the valve housing omitted.

As shown on the drawings:

The compressor chosen for illustrative purposes is, of a rotary typeand, in the form illustrated, is primarily intended to be belt driven asa part of domestic refrigerationapparatus wherein quietness andsmoothness ofv operation is an essential quality. The exact type ofcompressor is immaterial to the present invention which relates to adischarge or check valve that operates with the minimum of noisecompatible with the maximum efliciency in operation.

The illustrated compressor structure comprises a body 11 having acentral cylindrical bore 12 with outstanding end flanges 13, the facesof which are finished parallel to each other and at right ngles to thecylindrical bore, the perimeter of the flanges being finished concentricwith the bore to provide locating shoulders for end closures A backclosure 15 is shown in elevation in Fig. 1, while a front closure 16 isformed as a lubricontaining bearings for a compressor shaft'14.

cant reservoir or housing containing a'stumng box 17 andshaft seal 18 aswell as a shaft bearing 19 concentric with the cylindrical bore. Theshaft carries an eccentric 2.0 within the cylindrical bore, on whicheccentric is mounted a rotor or sleeve 21 which is so proportioned as tojust clear the cylinder wall at the position of maximum'eccentricity ofthe eccentric This sleeve floats on the, eccentric and is, therefore,free to roll within the cylindrical bore asit is oscillated therein bythe rotation of the shaft and eccentric. In practice it is approximatelystationary relative to the part generating the greatest friction, whichis usually the partition blade This blade is slidably mounted in a slot23 in the cylinder which slot terminates in a drilled hole 24 whichadmitslubricant back of the blade. A spring 25 is so positioned in aboss 26 as to act against the blade to supplement the pressure of thelubricant thereon to cause the blade to maintain contact with the sleeveor rotor 21.

End seals or covers 27 are applied to each flange 13 0f the body in theform of annular plates which make sealing contact with the rotor sleeve21 while having ample clearance from the shaft itself. The end seal onthe discharge side is formed with a discharge port 28 over which adischarge valve housing 29 is applied, the housing having an aperturedboss 30 into which a tube 31 is sealed which tube leads the dischargeinto the upper part of the reservoir.

16 above the lubricant level therein. The port 28 is on the dischargeside of the partition blade, while a suction passage 32 opens into thecompression space on the opposite side of the blade.

The discharge port 28 in the end cover is offset to one side of thehousing boss aperture 33, as best shown in Fig. 6, and is chamferedtowards the aperture. A flapper valve 34 is positioned over the port ina shallow pocket 35 in the housing and is pinned at 34' to. the cover atone end, the valve being thus ofiset relative to the housing aperture33. A relief slot 36 is cut in the housing along .the edge of the valvewhich is located substantially centrally of the aperture 33 because ofthis offset. A light coil spring 37 is so positioned in a pocket 38 asto engage the edge of the valve on the side opposite the relief slot.This arrangement causes the valve to open sidewise by a twistingmovement since one edge cylinder, into the slot 39 and thence to theport 28 rather than directly through the port 28 from the cylinder asheretofore. With this arrangement the clearance volume so providedserves to reduce wire drawing during the brief discharge intervalwherein the compressor pressure exceeds the back pressure normallyholding the discharge valve closed. The clearance space is also highlyadvantageous in case excess lubricant is present in the compressorcylinder as may be the case after a shut-down period. It has been foundby experiment that the clearance space should be directly adjacent thecylinder proper rather than in enlarged passages in the end closure.

The operation of the compressor proper is well known and hardly needsdescription. The discharge valve of this invention serves to preventback flow of compressed gases from the reservoir 16 and is normallyseated by such back pressure except during short intervals when thecompressor develops a pressure suflicient to unseat the valve. The valvethen opens sideways due to the oifsetilocation and unbalanced conditionintroduced by the spring 3''! so that the discharge from the port 28passes under the edge of the valve into the relief slot 36 and thenceinto the aperture 33 and tube 31. The clearance space provided betweenthe compressor cylinder proper and the port 28 is also an importantfactor in the quietness of operation of the valve as it reduces wiredrawing of the compressed gases and the impact of entrained liquids onthe valve.

. This application diifers from the copending,

Buchanan et ai. application Serial No. 509,812, entitled Dischargevalves, filed January 19,

1931, in that the valve opens by a torsionally twisting motion whereasin the copending application the valve opens by buckling up in thecenter. I

It will thus be seen that I have invented an improved compressordischarge valve that represents a great improvement in quietness ofoperation.

1am aware that many changes may be made, and numerous details ofconstruction may be varied through a wide range without departing y fromthe principles of this invention, and I therefore do not purposelimiting the patent granted hereon, otherwise than necessitated by theprior art.

I claim as my invention:

1. A discharge valve of the elongated strip type pinned at one end andadapted to control a valve seat in the outlet passage of a pump having acompression space completely swept by fluid im-.

pelling means, including a fluid receiving space in immediate proximityto the compression space and extending across the width thereof, saidfluid receiving space forming part of the outlet passage leading to thevalve-seat, said fluid receiving space being provided to cushion andreduce liquid hammer on both the pump and the discharge valve, andpressure means acting on one side of the elongated strip valveintermediate the length thereof and adjacent the discharge port wherebyto cause said valveto open by a transverse twisting movement in theregion of the valve port whereby to prevent valve slap.

2. A discharge valve of the straight strip type pinned at one end andadapted to control a valve seat in the outlet passage of a pump having acompression space completely swept by fluid impelling means, including afluid receiving space in immediate proximitylto the compression space,said fluid receiving space forming part of the outlet passage leading tothe valve seat, said fluid receiving space being provided-to cushion andreduce liquid hammer on both the pump and the discharge valve, andpressure means acting on one side of the straight strip valveintermediatethe length thereof and adjacent the discharge port wherebyto cause said valve to open by a transverse twisting movement in theregion of the valve port whereby to prevent valve 'slap.

3. A discharge valve of the elongated strip type pinned at one end andadapted to control a valve seat formed as a plane surface about theoutlet passage of a pump having a compression space completely swept byfluid impelling means, including a fluid receiving space in immediateproximity to the compression space, said fluid receiving space formingpart of the outlet passage leading to the valve seat, said fluidreceiving space'being provided to cushion and reduce liquid hammer onboth the pump and the discharge valve, and resilient loading meansengaging one side of said valve intermediate the length thereof andadjacent the valve seat to cause a torsionally twisting opening movementof the valve in the region of the valve seat. Y r

. JOHN L. KLABON.

